After confronting Bu'kaH in 2151, Jonathan Archer later told Trip Tucker that "I think I might have made a tactical error dealing with the Klingon woman. I asked her for help. She could see that as a sign of weakness." In response, Tucker asked if Archer had "been boning up on your Klingon psychology?" Archer then explained that "we've run into them three times, and every time they've wanted to destroy us. I'd love to figure out why." (ENT: "Sleeping Dogs")

After EnsignGarrovick was confined to his quarters for not firing his phaser quickly enough at the dikironium cloud creature on Argus X, Christine Chapel visited him, carrying a bowl of soup and a tape. Garrovick told her that he was not hungry, and instead wanted to know what was going on outside of his quarters. When Chapel told him that things were pretty chaotic, and that he was better off where he was, he began to go into a rant about how everything was his fault. In response, Chapel told him, "You know, self-pity's a terrible first course. Why don't you try the soup instead?" He again insisted that he was not hungry, at which point told him, "DoctorMcCoy thought you might say something like that," then held up the tape she was carrying and told him "this is his officially logged prescription for you. It has one word on it. Eat. Now if you don't follow his orders, Doctor McCoy could and possibly would have you hauled down to sickbay and fed intravenously," and then left. Upon returning to sickbay, she put the tape down. McCoy picked it up and read that it was "A Survey on Cygnian Respiratory Diseases", and asked, "I thought you took Garrovick some food. What were you doing with this?" Chapel responded, "Applying psychology." (TOS: "Obsession")

During the early 2350s, Benjamin Sisko and some friends where enjoying some free time at The Launching Pad when they were confronted by Solok and some other Vulcancadets, who "were doing research on illogical Human bonding rituals." Sisko and his friend didn't take kindly to that, and they got into a debate, and offered to solve the situation and prove that Humans were the equal of Vulcans by challenging Solok to a wrestling match, in which Sisko was easily defeated. Afterward, Solok took every opportunity to remind Sisko of the match by pointing him out as he walked across the campus, and later by writing five psychology papers about the match. Even after graduation, Solok continued to write about the match, having written over a dozen papers on Vulcan/Human comparative profiles by the mid-2370s, with each paper beginning with an analysis of their wrestling match. (DS9: "Take Me Out to the Holosuite")

After Troi had lost her empathic abilities in 2367, she was told by Beverly Crusher that her condition was "no different than if one of us suddenly going blind." Troi replied, "Doctor, you don't have to tell me, I understand the psychology," to which Crusher responded, "you may understand it, but you've never had to live with it." Troi was later visited in her quarters by William T. Riker, who stated "I don't have a psychology degree, but if you want to talk..." as his way of helping her out. Later, when Jean-Luc Picard needed Troi's assistance with understanding the two-dimensional lifeforms the USS Enterprise-D encountered, he told her "if there is a psychology to these creatures, we must discover it, if there is an explanation to their behavior, we must know it. Even in your current condition, you are the most qualified person aboard this ship to assist." (TNG: "The Loss")